1. Field of the Invention
This invention relates to air-powered tools, and more particularly to a hand-held turbine-driven orbital sander using a one-piece thermoplastic shaft and a machine screw inserted therein to mount a direct drive system, including two turbine halves, a counterweight, and a bushing drivingly connected to a platen.
2. Description of the Prior Art
Turbine driven tools have generally not used plastic drive shafts. U.S. Pat. No. 3,071,799 shows a turbine-powered cleaner in which a one-piece turbine is secured to one end of a shaft. A toothed pulley is secured to the other end of the shaft. Only the turbine is described as being plastic.
In conventional sanders using electric motors, a metal drive shaft is also typical, an exception being U.S. Pat. No. 3,345,784, which shows the use of an elastomeric flexible coupling between the motor shaft and a rotor. This coupling is merely a flexible intermediate element in the drive system.